The lowest dose of Ozempic (semaglutide) is 0.25 mg, administered once weekly by subcutaneous injection. This initial dose serves as a starting point for adults with type 2 diabetes mellitus, allowing the body to adjust to the medication whilst minimising gastrointestinal side effects. Ozempic is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed by the MHRA for glycaemic control. The 0.25 mg dose is not intended for long-term maintenance but forms part of a structured escalation protocol designed to balance therapeutic efficacy with tolerability. Understanding this dosing approach is essential for optimising treatment outcomes and supporting adherence to therapy.

Understanding Ozempic Starting Doses

Ozempic (semaglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed in the UK for the treatment of type 2 diabetes mellitus in adults. The lowest dose of Ozempic is 0.25 mg, administered once weekly via subcutaneous injection. This initial dose is specifically designed as a starting dose rather than a therapeutic maintenance dose, serving primarily to help the body adjust to the medication and minimise potential gastrointestinal side effects.

The Medicines and Healthcare products Regulatory Agency (MHRA) has approved Ozempic in pre-filled pen devices that deliver precise doses. Understanding the dosing schedule is essential for both patients and healthcare professionals to optimise glycaemic control whilst managing tolerability. The medication works by mimicking the action of naturally occurring GLP-1, which stimulates insulin secretion in a glucose-dependent manner, suppresses glucagon release, and slows gastric emptying.

Key points about Ozempic dosing:

• The 0.25 mg dose is the lowest available strength

• It is intended for initial treatment only, not long-term maintenance

• Dosing follows a structured escalation protocol

• The medication is administered once weekly on the same day each week

If you miss a dose, take it within 5 days of the missed dose. If more than 5 days have passed, skip the missed dose and take your next dose on the regularly scheduled day. You can change your weekly injection day if needed, provided at least 3 days have elapsed since your last dose.

Patients prescribed Ozempic should receive comprehensive training on injection technique and dose selection using the pen device. The structured approach to dosing reflects the medication's pharmacological profile and the need to balance efficacy with tolerability, particularly regarding gastrointestinal adverse effects that are common with GLP-1 receptor agonists.

Importantly, Ozempic is not indicated for people with type 1 diabetes or for treating diabetic ketoacidosis.

The 0.25 mg Dose: Initiation Phase

The 0.25 mg once-weekly dose serves as the initiation phase of Ozempic therapy, typically prescribed for the first four weeks of treatment. This lowest dose is not intended to provide full glycaemic control but rather to allow the body's physiological systems to adapt to the medication's effects. The 0.25 mg dose is a starting dose only and not intended for sustained glycaemic control. During this period, patients may notice some improvement in blood glucose levels, though the primary purpose is acclimatisation rather than maximal therapeutic benefit.

From a pharmacological perspective, starting at 0.25 mg allows gradual exposure to semaglutide's effects on the gastrointestinal tract and pancreatic function. The medication has a half-life of approximately one week, meaning steady-state concentrations are reached after four to five weeks of consistent dosing. This pharmacokinetic profile supports the four-week initiation period, allowing plasma levels to stabilise before dose escalation.

Common experiences during the 0.25 mg phase include:

• Mild nausea or reduced appetite (usually temporary)

• Gradual improvement in post-prandial glucose levels

• Adjustment to the weekly injection routine

• Minimal risk of hypoglycaemia when used as monotherapy

Patients should be advised that the 0.25 mg dose is a temporary starting point. It is important to maintain realistic expectations about glycaemic improvement during this initial month. Healthcare professionals should provide clear guidance that this phase is preparatory, with subsequent dose increases planned to achieve target HbA1c levels in accordance with NICE guidelines for type 2 diabetes management. Patients should continue monitoring blood glucose as directed and report any concerning symptoms to their GP or diabetes specialist nurse.

If you experience severe or persistent abdominal pain that could be pancreatitis, stop taking Ozempic immediately and seek urgent medical assessment.

Dose Escalation and Maintenance Levels

Following the four-week initiation period at 0.25 mg, the standard protocol involves escalating to 0.5 mg once weekly, which represents the first maintenance dose for many patients. This 0.5 mg dose provides clinically meaningful improvements in glycaemic control and is often sufficient for achieving treatment targets, particularly when combined with lifestyle modifications and other glucose-lowering therapies.

For patients requiring additional glycaemic control after at least four weeks at 0.5 mg, the dose may be increased to 1 mg once weekly. If glycaemic targets remain unmet after at least four weeks at 1 mg, a further increase to 2 mg once weekly may be considered. This 2 mg dose is the licensed maximum dose in the UK. Each escalation step follows the same principle: allowing adequate time for adaptation and assessment of therapeutic response.

The structured escalation pathway:

• Weeks 1–4: 0.25 mg (initiation dose)

• From week 5: 0.5 mg (first maintenance dose)

• If needed, after ≥4 weeks: 1 mg (maintenance dose)

• If needed, after ≥4 weeks: 2 mg (maximum licensed dose)

Clinical decisions regarding dose escalation should be individualised, taking into account HbA1c levels, tolerability, body weight changes, and the presence of other cardiovascular risk factors. NICE guidance emphasises the importance of regular review and adjustment of diabetes therapies to maintain optimal control.

If you miss a dose, take it within 5 days. If more than 5 days have passed, skip the missed dose and take your next dose on the scheduled day. You can change your weekly injection day provided at least 3 days have elapsed since your last dose.

Patients should never adjust their Ozempic dose independently; all changes must be discussed with and approved by their prescribing clinician, who will consider the full clinical picture including renal function, concurrent medications, and treatment goals.

Why Starting Low Matters for Tolerability

The rationale for initiating Ozempic at the lowest dose of 0.25 mg is firmly grounded in minimising gastrointestinal adverse effects, which represent the most common reason for treatment discontinuation with GLP-1 receptor agonists. Nausea, vomiting, diarrhoea, and constipation occur because semaglutide slows gastric emptying and affects gastrointestinal motility. By starting low, the digestive system can gradually adapt to these changes, significantly improving long-term adherence.

Clinical trial data demonstrates that gradual dose escalation substantially reduces the incidence and severity of gastrointestinal side effects compared to starting at higher doses. Most patients who experience nausea at the 0.25 mg dose find it mild and transient, typically resolving within the first few weeks. This tolerability profile improves treatment persistence, which is crucial for achieving long-term glycaemic control and reducing diabetes-related complications.

Benefits of the low-dose initiation strategy:

• Reduced nausea and vomiting: Gradual exposure allows physiological adaptation

• Improved treatment adherence: Fewer patients discontinue due to side effects

• Better patient experience: Manageable symptoms support confidence in therapy

• Lower hypoglycaemia risk: Gradual glucose-lowering effect, particularly important with concurrent sulfonylureas or insulin

Patients should be counselled that mild gastrointestinal symptoms during initiation are common and usually temporary. Practical strategies to enhance tolerability include eating smaller, more frequent meals, avoiding high-fat foods, and staying well-hydrated. However, persistent or severe symptoms warrant medical review.

People with pre-existing diabetic retinopathy, especially those on insulin, should be aware that rapid improvements in blood glucose control may temporarily worsen retinopathy. Report any new visual symptoms promptly and attend regular eye screening appointments.

There is also an increased risk of gallbladder disease with GLP-1 receptor agonists. Seek medical advice if you experience persistent pain in the upper right abdomen, fever, or yellowing of the skin or eyes.

When to Discuss Dose Adjustments with Your GP

Regular communication with your GP or diabetes care team is essential throughout Ozempic therapy, particularly regarding dose adjustments. Scheduled reviews should occur after the initial four-week period at 0.25 mg, and subsequently when considering each dose escalation. These appointments allow assessment of glycaemic control through HbA1c testing, evaluation of tolerability, and discussion of treatment goals.

Patients should proactively contact their GP or diabetes specialist nurse if they experience persistent or severe side effects at any dose, including ongoing nausea lasting beyond two weeks, repeated vomiting, severe abdominal pain, or signs of pancreatitis (severe upper abdominal pain radiating to the back). If pancreatitis is suspected, stop taking Ozempic immediately and seek urgent medical assessment. Additionally, symptoms of dehydration from gastrointestinal effects—such as dizziness, reduced urination, or extreme thirst—require prompt medical attention. These may necessitate temporary dose reduction or additional supportive measures.

Specific situations requiring GP discussion:

• Inadequate glycaemic control: If blood glucose remains elevated despite four weeks at current dose

• Hypoglycaemia: Particularly if taking sulfonylureas or insulin concurrently (dose adjustments of these medications may be needed)

• Significant weight loss: Unintended excessive weight reduction

• Planned surgery or acute illness: Temporary treatment modifications may be necessary

• Pregnancy planning: Ozempic should be discontinued at least two months before conception

• New medications: Potential drug interactions require review

• Visual changes: Especially if you have pre-existing diabetic retinopathy

• Symptoms of gallbladder disease: Persistent right upper abdominal pain, fever, or jaundice

Never adjust your Ozempic dose independently or discontinue treatment without medical guidance. Abrupt cessation can lead to deterioration in glycaemic control. Your healthcare team will consider multiple factors when determining optimal dosing, including renal function, cardiovascular status, and overall diabetes management strategy aligned with NICE quality standards. Regular HbA1c monitoring, typically every three to six months, provides objective evidence to guide dose optimisation decisions.

If you experience any suspected side effects from Ozempic, report them via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk or through the Yellow Card app.

Frequently Asked Questions